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The air on the N.W. side of the Desert of Arabia, whence the Sumyel comes, assumes for some minutes before it is felt a dusky hue. It moves with considerable velocity, and is accompanied with a hissing noise. Those who are attacked by this wind are generally destroyed. Some persons however have escaped its dreadful effects, who, on perceiving its approach, have thrown themselves prostrate on the ground, and enveloped their heads in many folds of cloth, or those who have put their faces close to the ground in the dust until it has passed. Camels are said to be sensible of its approach, and take this method of their own accord to avoid its fatal effects. Sir J. Chardin observes likewise, that persons who are killed by it are not much changed in external appearance, but that their limbs are very easily separated from the body.
A further though not a better account of this wind has also been published in the Annual Register, Vol. IX. taken from the relation of Mr. Vanderhulse, who was long resident for the Dutch at Ormuz, and who came from thence to Bombay in the year 1763.
This seems to be little more than a variety of the Samiel ; and the term itself may indeed be derived from the same root. It is described by Mr. Bruce as an excessively hot wind peculiar to the country of Abyssinia. He frequently felt its influence; once when he and his company were on their way to Rascid, when they became so enervated, and their stomachs so weak, with such violent head. achs, that they were incapable of pitching their tents; but each wrapping himself in his cloak, resigned himself immediately to sleep. On the 13th of October, when at Chendi, to use his own words, “ the poisonous simoom blew as if it came from an oven; our eyes were dim, our lips cracked, our knees tottering, our throats perfectly dry, and no relief was found from drinking an immoderate quantity of water. The people advised me to dip a sponge in vinegar and water, holding it before my mouth and nose, and this greatly relieved me.” Mr. Bruce does not say from what quarter the simoom blows. (Editor from BRUCE.
3. Mistral or Circius, and Autun. The wind known in Provence, under the name of Mistral or Circus, comes from the Alps to the N.W. It is supposed to con. tribute greatly to the salubrity of the air, by dispelling the vapours from the marshes and stagnant waters in the southern parts of Provence and Languedoc, where also, as Mr. de Saussure observes, it subjects the inhabitants to great inconvenience, and some. times to considerable losses.
This excellent philosopher imputes it to three causes :
First, The situation of the Gulf of Lyous, which is terminated by a sort of tunnel formed by the Alps and the Pyrennees, and whose sides, therefore, are the principal scenes of its ravages. An the winds between the N. and the W. are united in this gulf, which by Aulus Gellius is called Circius. (Lib. II. cap. 22. See also Pliny, (Lib. II. 46.)
The second is, that this gulf, being to the S. is lower and warmer than the parts adjacent, and as the inferior current of air goes always from the cold to the warm point, the Gulf of Lyons must necessarily be the centre of violent winds, both from the E. and the W.
The third cause is nearly included in the two preceding.
In opposition to the Mistral, another singular wind blows from the east or south-east, which is called autun. It is first perceived near Narbonne, and at Castlenaudari is very violent: this wind, which is hot, produces head-achs, with loss of appetite, and seems to swell the whole body. In the eastern part of Languedoc is frequently felt a cold and very strong north wind, which follows the course of the Rhone, in the valley through which it runs, from north to south, and is called bise, or black. Sometimes, in direct opposition to the latter, blows a sea-wind, which is usually accompanied with a drizzling rain; but when dry, has the same morbid effects as the autun in Upper Languedoc; beside, in the heat of summer, from the coast of Leucate to the Rhone, sea.breezes constantly set in, at nine or ten o'clock in the morning, and, to the great refreshment of the air, last till about five in the evening, Lastly, it is also observable, that at the foot of the Pyrennees, near the village of Bland, in a narrow valley, wholly environed with mountains, except towards the north-west, and through various channels two or three hundred paces wide, blows a very cold west, or north-west wind, which prevails chiefly in the sum. mer, and then only at night. In clear warm weather this wind is much brisker than in a dense cold atmosphere. In summer it cools the whole valley, and in winter prevents hoar frost; and as it blows only in the night the inhabitants of the village of Bland can winnow their corn at no other time.
EDITOR from De Saussure.
Occasional Winds: as Hurricanes, Tempests, Tornados, and
1. Hurricanes of the West Indies, and their Causes, in a
Communication from Capt. Langford to Mr. Bonavert. It has been the custom of our English and French inhabitants of the Caribee islands to send about the month of June, to the native Caribees of Dominico and St. Vincent, to know whether there would be any hurricanes that year; and about ten or twelve days before the hurricane came, they would constantly send them word; and it very rarely was erroneous, as I have observed in five hurricanes, in the years 1657, 1658, 1660, 1665, and 1667. Fron one of these Indians, I had the following prognostics :
1. All hurricanes come either on the day of the full, change, or quarters of the moon. 2. If it be to happen on the full moon, observe these signs, during the change : the skies will be turbulent, the sun redder than usual, a great calm, and the hills, clear of clouds or fogs over them, which in the high lands are seldom so: likewise in hollows, or concaves of the earth, or wells, there will be a great noise, as of a storm, and at night the stars will look very large with burs about them, and the north west sky very black and foul, the sea smelling stronger than at other times; and sometimes for an hour or two of that day the wind blows very hard westerly out of its usual course. On the full of the moon you have the same signs, with a great bur about the moon, and frequently about the sun. The same signs must be observed on the quarter days of the moon, in July, August, and September ; the months when the hurricanes are most prevalent; the earliest I ever heard
of, was the 25th of July, and the latest the 8th of September ; but the usual morith is August.
The method of avoiding the danger is to keep the ship sailable, with good store of ballast, the ports well barred and caulked, the top-masts and tops down, the yards laced a-port, keeping the doors and windows of the ship fast, and she will lie as ell as in other storms; thus the ship being in readiness, they may stay in the road till the storm begins, which is always first at north, so to the north-west, till it comes round to the south-east, and then its fury is over. So with the north wind they may run away to the south, to get themselves sea-room, for the drift of the south-west wind, where it blows very fiercely. By these means, I have, by God's blessing, preserved myself in two hurricanes at sea, and in three at shore, greatly to my advantage, as I lost not a sail, yard, or mast in two great hurricanes.
The causes of these hurricanes, according to experimental ob. servations of my time, are these :
1. It is known to men of experience, that to the southward of the tropics there is constantly a trade-wind, or easterly wind, which goes from the north to the south-east all the year round; except where there are reversions of breezes, and inlets near the land; so that when this hurricane, or rather whirlwind, comes in opposi. tion to the constant trade.wind, then it pours down with such violence as exceeds any storms of wind. In the hurricane at Nevis, I saw the high mountain that was covered with trees left in most places bare.
2. It is remarked by all men, that have been in those parts where the sun comes to the zenith, that at his approach towards it, there is always fair weather; but at his return southwards, it oc. casions, off the north parts of the equinoctial, generally much rain and storms, as tornadoes, and the like; which makes the wind in the tornado come on several points. But before it comes, it calms the constant easterly winds; and when they are past, the easterly wind gathers force again, and then the weather clears up fair.
3. The wind being generally between the tropics and the equator easterly, unless at such times as before mentioned : meeting with the opposition of these hurricanes, which come in a contrary course to that trade-wind, causes this violent whirl.wind, on the sun's leaving the zenith of Barbadoes, and these adjacent islands; by which the easterly wind loses much of its strength; and then the west wind, which is kept back by the power of the sun, with the greater violence and force pours down on those parts where it gets vent. And it is usual in sailing from Barbadoes, or those islands to the north, for a westerly wind, when we begin to lose our easterly wind, to have it calm, as it is before hurricanes : and then the wind springing up, till it comes to be well settled, causes the weather to be various; but after the settled westerly wind comes fresh, they have been constantly without those shufflings from point to point.
Ilere it is to be observed, that all hurricanes begin from the north to the westward, and on those points that the easterly wind blows most violently, the hurricane blows most fierce against it; for from the N. N. E. to the E. S. E. the easterly blows freshest; so does the W. N. W. to the S. S. W. in the hurricane blow most violent; and when he comes back to the SE, which is the com. mon course of the trade.wind, then it ceases of its violence, and so breaks up. Thus I take the cause of hurricanes to be the sun's leaving the zenith of those parts towards the south: and second. ly, the reverse or rebounding back of the wind, which is occa. sioned by the calming of the trade-wind.
But it will be objected, why should not this storm be all over those parts of the West Indies, as well as Barbadoes and the Leeward.islands ? To which I answer, that it has in about 25 years of my experience, taken its course from the Bermudas to the Caribees; but seldom or never carries such a breadth as from the latitude of 16 to '32 degrees, which are the latitudes of the places; but it has been observed, that when hurricanes have been in Martinico, which is within two degrees of latitude, and two degrees longitude, according to the miles of that circle, yet no hurricane has been in Barbadoes; nor could I ever call any of the former storms at Barbadoes hurricanes, till that last year in 1675. Again it has heen noted, that hurricanes have done the like to the northwards: for when the hurricane has been in Antigua and St. Christopher's, those ships that were only in the latitude of twenty degrees, had no hurricane, but constant westerly winds, reason. ably fair, and then there were no hurricanes in Bermudas; and